I have just finished a rear suspension refurb on the M3.
I wanted to strip it down to check for wear and tear from age and V10 abuse and replace / strengthen as necessary, I was pleasantly surprised, the rubber bushes were a bit aged, the wheel bearings were slightly noisy but the driveshafts seemed o.k. so I decided to just refurbish.
It took a day to strip it all out, I think I got off lightly with seized bolts etc as most of it had been taken apart by Glenn during the initial rebuild.
I opted to take discs, calipers and the diff off in situ, the diff is very heavy (35kg ?) this left the beam and trailing arms which are relatively manageable
I removed the trailing arm bushes with a version of the wiki diy removal tool, I used a 30mm deep reach socket instead of the pipe as I had one to hand. they came out easily after a warm with the hot air gun.
If you are doing your beam bushes it is so much easier with one of these;
The beam bushes also came out easier with a heating, I believe this tool can remove and install bushes in situ.
some of the bits for the refurb;
I opted to go for satin black powder coating, I think it came out really well;
I left some old bolts in to protect the threads and cut some 10mm plywood discs to protect the bearing housings.
The diff had a slight oil leak, I believe it was from the drain plug, I took the cover off, cleaned the diff out, changed the gasket, speedo sensor retaining plate and the plug crush washers. It was then painted.
Before reassembly I changed all the hard rear brake lines, flexible Black diamond brake hoses and the main fuel line including mounting clips. The fuel / brake line clips were mostly seized, I had to drill and tap the old screws out, not a nice job !
I started reassembly by fitting the beam complete with Powerflex bushes, I then fitted the trailing arms, diff and brakes (which have been refurbished previously )
The wheel bearings were changed ( SKF ) and the driveshaft c.v's were cleaned out, checked, regreased and fitted with new GKN Lobro c.v joint boots from ecp;
http://beta.eurocarparts.com/ecp/c/BMW_ ... 81e&000445
Most boots are too big for the wheel side, they rub on the shock absorber. The diff side kit fit fine apart from the bolts which had no tensile markings on them, I brought some proper ones, the people who did my propshaft recommended 10.9 tensile strength for drivetrain bolts.
For the wheel side I removed the rubber boot from the kit, it has the correct circular seal to fit on the existing c.v metal cover. Basically I paid £19.80 for the kit and only used the rubber boot for the wheel side, still cheaper than the £60 BMW wanted per boot kit.
The diff was filled with 1.7 litres ofCastrol Syntrax 75w 140 lsd oil.
I also fitted a temperature sensor to the diff as my vdo oil temp gauge was not being used because the Awron dash vent gauge provides this info.
I used an e30 engine coolant temp sender as this over reads by about 50% on the vdo gauge, it also allows the fitment of the correct 'click' type oem plug which should satisfy Danthe's oem plug fetish !
The over read is required because the vdo gauge does not start reading until 60 degrees c. After a 30 mile test drive the diff temp was showing 65 to 70 degrees c so about 40 degrees actual which is in line with the gearbox which runs at about 50 degrees c
I reckon the cost for parts is about £500 which includes the powerflex, powdercoat, boots, brakeparts etc and all new clips, bolts and fittings.
A few shots of the car as it stands;
